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2651 router dlci limit ??

Hi All,

Can anyone expain the dlci limitation suggested from the following links:

Excerpt follows:

"The maximum DLCIs per router (not interface) platform guideline, based on extrapolation from empirical data established on a Cisco 7000 router platform, are listed below:

Cisco 2500: 1 X T1/E1 link @ 60 DLCIs per interface = 60 total

Cisco 4000: 1 X T1/E1 link @ 120 DLCIs per interface = 120 total

Cisco 4500: 3 X T1/E1 links @ 120 DLCIs per interface = 360 total"

I've seen the mtu-13/5=max dlci's (for ansi) formula but can't seem to find what the 3x120 DLCI per router (4500) figure above is based on, well apart from "extrapolation from empirical data" !!! Aaarrggghhh.

We'd like to configure a high number of dlci's on several v11 ints on a 2651, anyone have any figures?




Re: 2651 router dlci limit ??

The main factors that can affect the number of DLCIs that can be configured on an interface are

1)LMI Type.


3)interface descriptor block


5)Limitation by the router

What you are mentioning here is the last factor. The values you are mentioning is arrived based on the extrapolation form the empirical data only.And moreover ,its clearly mentioned in that documnet that it is just a guideline.Its a theretical limitation only.

You can increase the MTU to support a larger full status update message from the Frame Relay switch. If the full status update message is larger than the interface MTU, the packet is dropped, and the interface giant counter is incremented. When changing the MTU, ensure the same value is configured at the remote router and intervening network devices.